Electrical coil apparatus



April 21, 1925. 1,534,959 L. L.' ISRAEL (NOW BY JUDICIAL CHANGE OF NAME L. L. JONES) ELECTRICAL COIL APPARATUS Original Filed Aug. 5, 1919 I5 Sheets-Sheet 1 WITNESS: INVENTOR.

5% MM) 31% BM 14/ ATTORNEY.

April 21, 1925. 1,534,959 L. L. ISRAEL (NOW BY JUDICIAL CHANGE OF NAME L. L. JONES) ELECTRICAL COIL APPARATUS Original Filad'Aug. 5, 1919 3 Sheets-Sheet 2 I N VEN TOR.

WI TNESS:

A; ATTORNEY.

April 21, 1925. 1,534,959 1.. L. ISRAEL (NOW BY JUDICIAL CHANGE O NAME L. L. JQNES) ELECTRICAL U0; APPARATUS Original i-ilod Aug. 5.. 1919 5 Sheets-Shut 5 I N VEN TOR.

do; ATTORNEY.

WI TNESS:

Patented Apr. 21, 1925.

UNITED STATES PATENT OFFICE.

LESTER L. ISRAEL, NOW BY JUDICIAL CHANGE OF NAME LESTER L. JONES, OF ORA DELL, NEW JERSEY, ASSIGNOR TO EM'IL J. SIMON, OF NEW YORK, N. Y.

ELECTRICAL COIL APPARATUS.

Application filed August 5, 1919, Serial No. 315,386. Renewed April 13, 1923.

To all whom it may concern:

Be it known that I, LESTER L. ISRAEL, now by judicial change of name LESTER L. Jones, a citizen of the United States, residing at Oradell, in the county of Bergen and State of New Jersey, have invented certain new and useful Improvements in Electrical Coil Apparatus, fully described and represented in the following specification and the acconu'ianying drawings, forming a part of the same.

The invention relates to electrical coil structures, and especially to adjustment means for such coils. The general object is to provide improved and simplified means t'or effecting a plurality of relatively broad adjustments of a coil, or step-bystep adjustments of definite interval, and for effecting a continuous, or fine ad'- justment, of indefinite gradations, for each of the step adjustments.

Coil mechanism embodying the invention is useful in various kinds of electrical apparatus. In certain of its embodiments the invention is especially advantageous in wireless transmission apparatus. The invention will be herein described with reference to its utility in that art.

As adapted for radio-transn'iitters, the invention provides an improved wavechanging apparatus. especially suitable for transmitters ot the quenched-spark type. although it is adaptable to other types of transmitters.

An important object is to provide for continuous, or indefinite variable, tuning of the antenna circuit at'or in the region of a number of different wave length adjustments,-by manipulation of one controlling device. Another object is to provide means by which the single controlling handle is engaged with the proper tuning element by the action of the wave changer switch, and is at the same time disengaged from all the other tuning elements. A further object is to provide means by which the continuous tuning of the antenna at or near one ave length is independent otthe tuning for each other wave length, so that tuning for a series of three or more wave lengths may be rapidly efiected, each independently of the other, and in any order. A further object is to simplify, and increase the efliciencv of the electrical circuit by eliminating a number of high tension leads in the autenna circuit.

In previous forms of apparatus, the primary inductance coil. the antenna coupler coil and the antenna load coil have been provided with a plurality of contacts. and switches have been provided to connect with these contacts to vary the inductance of the different coils simultaneously, and in some cases a common switch-operating mechanism has been provided to move all the switches simultaneously to insure the proper simultaneous adjustment of the coils. A plurality of independent tuning devices or va riometers corresponding to the number of wave lengths have been provided for the antenna inductance, and each of these devices has been controlled by a separate handle. To tune for any given wave length. therefore, the operator has always been obliged to notice carefully the position of the wave length switch in order to determine what wave length was effective, and then to note the variometer handle corresponding to that wave length in order that the proper tuning handle might be manipulated. In case of an error in selecting the handle. there was delay in tuning, and also frequently the tuning of the antenna for other wave lengths was interfered with needlessly. requiring their readjustment.

In previous systems also it has been necessary to provide high tension leads connecting the wave length switch contacts with the sliding tuning devices or variometers. It has been diflicult to dispose of these leads, so that they would not spark to the coils, and so that they were outside the magnetic field of the coils.

In my invention the first difficulty is avoided by providing a single manipulating device for the various tuning devices or variometers, and in whatever position the wave changing switch may be, manipulation of the tuning device will always ettect tuning for that wave length, because the positioning of the wave-changing switch automatically connects the controlling device with the corresponding variometer. The second difliculty is avoided because the high tensiouleads are eliminated and one metallic part serves as the wave length switch arm and' connector.

The objects, characteristics and advantages of the invention are further explained, so far as is necessary, in connection with the following detailed description of a reprcsentative structure embodying my invention. At'ter considering this, it will be evident to persons skilled in the art that the invention may be GlIllNXllQd in different structures, and I do not limit myself to details except as claimed.

Fig. 1 is a diagram of the radio-frequency cir nit of a wireless telegraph transmitter of the quenched-spark type, embodying the invention.

Fig. 2 is a section in an axial plane of the aerial wave changing and tuning mechanism.

Fig. 3 is a transverse section of the same.

Fig. 4 is a sectional detail of the sliding contact and connector, and part of one of the variometer arms.

P is the primary inductance with fixed contacts p. S is the secondary inductance or couplingcoil with fixed contacts '8. Movable contacts 7), s respectively, for these coils are mechanically connected as diagrammatically indicated by shaft 5 to be moved together. L is the antenna load COll, in this case consisting of a flat strip formed in a helix, although it may be of any suitable form and arrangement. Within this coil is a rotatable sleeve 6 of insulating material, and within the sleeve is an endwise reciprocable and rotatable cylindrical rack 7 carrying a movable contact and connector 8 which serves to make the circuit connection for the different wave lengths and at the same time to connect the tuning devices for the different wave lengths mechanically with the tuning handle 9. A pinion 10 effects the endwise reciprocal movement of the rack 7, and this pinion may be connected to move in unison with contacts 72', s by suitable mechanical connections, such as shaft 11 and universal joint 12.

Load coil L is located between suitable insulating end plates 13, 14, and is supported by insulating struts 15 which connect the plates. Secured to plate 14 is a fitting 16 which provides a hearing at 17 for one end of sleeve 6. The other end of the sleeve has a bearing in a fitting 18 supported by end plate 13.

Variometer or tuning arms 20 are provided in number equal to the number of wave lengths. Each of these arms has a clip or sliding contact 21 comprising pairs of fingers 22 embracing the coil strip. These fingers are carried on pivot 23, and the pivot has a stem 24 extending into and secured in the end of an inner sleeve 25 of the variomcter arm. Sleeve 25 telescopes in an outer sleeve 26. The contact is urged out into proper engagement with the coil by a spring 27 located within the sleeves and bearing against the bottom of sleeve 2(i-and against a plug 28 in the outer end of sleeve This plug also accommodates the pin 24 of the contact pivot. The inner end of sleeve 26 is formed into a fork 2!), the ends of which are connected pivotally by means of eyes 30 to trunnions 31 on a divided ring 32 which embraces sleeve (3 and is rcvoluble thereon. Each ring may be in two parts secured together by screws 33.

The conductive continuity of the ring is preferably broken by inserting in the ring at at least one point of its circun'iferencc an insulating disk or washer 33, and also properly insulating the adjacent screw 33 with insulating sleeves 33 and washers 33, to prevent the circulation in the ring of electrical currents caused by induction.

The rings have inwardly projecting members 34 located between shoulders 35 on sleeve 6 to locate the rings lengthwise on the sleeve. Each of the inwardly projecting members 34 has, usually at two opposite points of its circumference, notches 36 providing shoulders for engagement with connector 8.

Cylindrical rack'l', beginning at the outer end and for the greater part of its length is tubular. At the other end adjacent to connector 8 the rack extension 40 on the end of which is secured a disc 41 of insulating material, having a sliding fit in sleeve 6 to guide the end of the rack in its reciprocal movement within the sleeve. Disc 41 has secured to it at one side a lug 42, fitting in a longitudinal slot 43 in one side of sleeve 6, thus causing the sleeve to turn in accordance with rotation of the rack. Connector 8 is in the form of a spring-pressed plunger. movably mounted in a sleeve 44 located in a transverse bore of rack extension 40. A spring 45 located within sleeve 44 urges the connector plunger outward in slot 43. A pin 46 engaging slots 47 in one end of sleeve 44 limits outward movement of the plunger. The plunger 8 moves along in slot 43 in accordance with endwise movement of rack 7. lVhen it comes opposite any inwardly projecting annulus 34 of one of the variometer rings 32, the plunger is depressed slightly, and it the rack is retained in that contact is made with the corresponding variometer arm corresponding to the Wave length adjustment of the primary and secondary inductance coils P and S. If sleeve 6 is then rotated, plunger 8 slides around the inner periphery of annulus 34 until it encounters one of the notches 36, whereupon it enters the notch, and then the variometer arm is coupled to the sleeve mechanically has a plain round solid position, electricalv and may be rotated with the sleeve to tune the load coil for the corresponding wave length. The sliding contact 21 of the varionie-tcr arm has suilicient frictional engagcment with the coil to normally hold the variometer arm in position and permit the sleeve 6 to turn within its ring 32 without afi'ccting the variometer arm, unless plunger 8 is in engagement with a notch of corresponding ring 32, and in that case the friction of the contact 21 is overcome and the arm moves with the sleeve, as above described.

Evidently, by successive positioning of rack 7 and plunger 8, connection may be effected with all of the variometer arms in turn, and each of them may be adjusted in the manner described. When all of the a rms are once adjusted tocorrectly tune the aerial circuit with the inductance coils in accordance with variable conditions of the aerial, the load depth of a ship on which the apparatus is placed, or other variable conditions, all of the different tunings will he maintained so long as sleeve 6 is not involved, and the wave length may be quickly changed at will without affecting tuning by reciprocating rack 7.

The pivoted fork connection of the variometer arms with their rings 32 permits each arm to swing in an axial direction over approximately one-third of the coil. This in turn permits the normal angular positioning of certain ones of the variometer arms, as shown in the drawing. in order to locate the coil, sleeve 6, and associated parts in the most convenient relative positions. The telescoped arrangement of the parts of the variometer arms, and springs 27 serve not only to provide the necessary frictional contact with the coil. but to permit the variation in length of the variometer arms due to their different angular positions.

The. tubular end of rack. 7 has a sliding fit in titling 16. Tu the open end of the rack is secured a block having an angular or splincd hole. and in this hole is slidably fitted a rod 51 having a similar cross-section. The outward end of the rod is secured in an insulator 52. A stem 53 is secured in the other end of the insulator and tuning wheel or handle 9 is secured on this stem. A bracket 54 is located on a plate 55 secured to plate 14 by struts 56, and this bracket surrounds insulator 52 and has abearing 57 for stem 53. and also prevents end movement of handle 9 and rod 51 in an obvious way. Plate 55 has a central hole 58 to accommo date the end of rack 7.

Pinion 10 has its shaft 60 mounted in bearings formed in extensions 61 ot fitting 1G.

The binding post or connection 65 on rear plate 13 has metallic connection with the rear end of the load coil. and fitting 16 has a binding post or connection (36.

The electrical circuit of the antenna inductance in the position of parts shown in Fig. 2 is from the aerial to binding post (35, through one-half of the rear turn of the inductance coil L, then through the rarimueter contact sleeves and ring 32 to connector H, through rack 7 to fitting l6 and binding post- 66, and then as shown in the diagram, Fig. 1, through coupling coil S to ground. It will be noted that there is a liberal air gap between rack 7 and the other rings 32 which are in electrical contact with the coil. This is sufficient to prevent leakage of current from unused turns of the coil in which potential is created by induction. The weakest insulation path is along sleeve 6. hen the rack is moved forward so that connect or R is in engagement with the foremost ring and all of the inductance coil is in use. In

convenient design of the apparatus, it is.

practicable to provide at least five inches total insulation distance along this sleeve to the rearmost ring, which is sntlicient to prevent leakage or sparkover due to the high voltages along the coil. which are brought to the sleeve by the variometer arms 20. \Vhen the connector 8 is in engagement with any of the other rings 32, the insulation path is shorter, but also the voltage developed is proportionally less. Furthermore, the spacing of the rings may obviously be sutficient to prevent sparkover between adjacent rings.

Insulator 52 serves to insulate the high tension electrical system from tuning handle 9, which is kept at ground potential by its metallic connection with the grounded bracket 54.

In some cases it is desirable to short circuit unused portions of the coil to avoid phenomena known as end effect. due to induction. This is done by providing the outermost ring 32 with a contact finger 70. which has a sliding engagement with peripheral part 71 of metal fitting l6. \Vhen contact 8 is in engagement with any variomcter ring other than the outermost one. the unused part of the coil is short circuited through the outermost variometer arm, its ring 32. contact 70, fitting 16. rack 7 and contact 8.

Similar principles of construction and arrangement may be applied to systems employing flat or conical spiral coils, with suitable modifications of mechanical details to suit such arrangement.

It will be understood from the foregoing that before commencing sending. the operator may turn the antenna coil for all wave lengths by moving the wavechanging switch to successive positions. and in each of its positions rotating the turning handle 9 appropriately to suit the present condition of the aerial circuit. He may then use any wave length immediately by moving the wave-changing switch, and in whatever position it may be he can retune the load coil lio whenever it may be necessary by moving handle 9 without the possibility of interfering withtuning for other wave lengths.

What is claimed is:

1. Electrical-coil adjustment apparatus, comprising a coil, a plurality of movable contacts engaging the coil at different points, a controlling device for adjusting said contacts, and means for electrically connecting the controlling device with the contacts selectively.

2. Electrical-coil adjustment apparatus, comprising a coil,'a plurality of movable contacts engaging the coil at different points, a controlling device, and means for establishing electrical connection with the coil through the individual contacts selectively, and simultaneously effecting mechanical connection between the selected contact and the controlling device for the adjustment of that contactwithout disturbing the adjustment of the other contacts.

3. In electrical-coil adjustment appara tus, the combination of a coil, a rotatable member near the coil, a plurality of variometer devices in disconnected relation to the rotatable member and each having movable contact with a portion of the coil, a connector, means for shifting the connector to engagement with thevariometer devices selectively,,and a single controlling member operative to adjust the variometer device with which the connector'engages without disturbing the other variometerdevices.

4. In electrical-coil adjustment apparatus, the combination of a coil, a rotatable sleeve near the coil, a plurality of variometer devices in disconnected relation to the rotatable sleeve and each having movable contact with a portion of the coil, a longitudinally and rotatably movable member 7 within the sleeve, a connector carried by said member to engage said variometer devices selectively, means for moving said member longitudinally to effect said selective engagement, and a rotatable controlling device to rotate said member to effect coil adjustment. through the variometer device with which the connector is engaged without disturbance of the other variometer'devices.

5. In electrical-coil adjustment apparatus, the combination of a coil, a rotatable sleeve adjacent to the coil, the sleeve having a longitudinal slot, a member mounted within the sleeve for relative reciprocal and rotary movement, a yieldable connector carried by said member and located in said slot, means for moving said member longitudinally, independent means for rotating said member, variometer rings definitelyspaced lengthwise of the sleeve and rotatable relatively thereto, said rings having shoulders to be the combination with :1

engaged by said connector, and variometer arms each connected with one of said rings and a movable electrical connection with a portion of the coil.

6. In electrical-coil adjusting apparatus, the combination with a coil, of a shit-table member, means positioned by said shiftable member for selectively est. blishing electrical connection with the coil at a plurality of relatively widely separated points, and means operated by further positioning of said member for varying by indefinite gradations the adjustment of any connection selected.

7. I11 electrical-coil adjusting apparatus, the combination with a coil, of a shiftable conducting member adjacent to the coil, and shit'table connecting means comprising a part rotatable about the axis of said conducting member, an arm pivotally connected to said part, and a contact member carried by the arm and engaging the coil.

8. In electrical-coil adjusting apparatus coil,.of a shiftable conducting member adjacent to the coil, shiftable connecting means comprising a part rotatable about the axis ofsaid conducting member, an arm pivotally connected to said part, and a contact member carried by said arm and engaging the coil, the arm being formed to permit its length to vary automatically in accordance with its angularity.

9. An adjustable coil mechanism, comprising a coi1, a rotatable controlling memer, a ring revoluble about the controlling member, a fork pivoted to the ring, a yieldably extensible arm carried by the fork, and a contact memberat the end of the arm engaging the coil.

10. In electrical-coil adjusting apparatus, the combination with a coil, of connecting. means comprising a member movable for making broad adjustment of the amount of the coil connected in circuit and otherwise adjustable for fine adjustment by varying by indefinite gradations the amount of the coil inserted.

11. In electrical-coil adjusting apparatus, the'combination with a coil, of'connecting means comprising a member movable axially of the coil for making broad adjustment of the amount of the vcoil connected in circuit and movable rotatably to vary by indefinite gradations the amount of the coil inserted.

In testimony whereof I have hereunto set my hand in the presence of two subscribing witnesses.

LESTER L. ISRAEL. 

